Hi Steve,
according to the SCORM specification when the lesson_status in SCORM is set to "passed", "complete" or "failed" these are completed or finished attempts at the SCORM and allow the user to generate a new attempt rather than re-enter the previous attempt.
You may need to modify how your SCORM package is authored so that it saves the value "incomplete" in the lesson_status instead of "failed"
this might also be useful:
https://docs.moodle.org/en/SCORM_FAQ#Handling_of_Multiple_Attempts